Résumé
Using lactoferrin as the specific ligand, we developed a simplified method for preparation of molecular conjugate for gene delivery. Replacement of column chromatography and dialysis by one step centrifugal filtration (Centricon, cut off size : 30,000), resulted in the rapid purification of bovine lactoferrin/polylysine (bLf/pL) and human lactoferrin/polylysine (hLf/pL) conjugates and easy separation of unconjugated polylysine. The Lf/pL conjugates prepared by this method efficiently transferred the reporter genes, CAT and LacZ gene, to HeLa and hepatic cells. The bLf/pL and hLf/pL conjugates could transfer the reporter genes to various hepatocytes including primary mouse hepatocyte, Hepa 1-6, SK-Hep1 and Chang liver, but not to NIH 3T3 mouse fibroblast cells, indicating that the Lf/pL conjugates conferred hepatocyte-specific gene transfer. The bLf/pL and hLf/pL conjugates prepared in the present study exhibited higher transfection efficiencies for mouse and human hepatocytes than the commercially available transferrin/polylysine (Tf/pL) conjugate.